A lot of systems of this kind are known. In many known coupling ring systems for ostomy equipment one of the annular members is provided with one or more substantially axial slots and the other with axial projections co-operating therewith. The details of such systems may vary much, but in all embodiments the grooves and projections are provided with co-operating tightening surfaces and frequently also with co-operating annular beads and sometimes also grooves resisting release of the two ring members from each other. Examples of such systems may be seen in, e.g., DE patent specification No. 1 105 558 and GB specifications Nos. 1 099 455, 1 571 657, 1 586 823, 1 586 824 and 1 583 027.
It has been found that the co-operating holding surfaces extending substantially in the axial directions of the annular member do not always adequately ensure against release of the coupled state at unintentional pull of the bag occurs, even if such pull is moderate and fairly evenly distributed over the perimeter of the ring coupling. When the bag is filled, it may itself cause a one-sided, oblique pull on a limited part of the ring and this may cause a local leakage in the coupling, possibly resulting in escape of intestinal gases accumulated in the bag and sometimes also liquid.
The unintentional release of the ring coupling upon a fairly uniform pull is avoided in a construction known from U.S. Pat. No. 4,078,567 (the purpose of which, incidentally, is another) wherein that the coupling member adapted to engage the abdomen of the patient is provided with an annular groove with a radially outwardly situated opening, and wherein that the edge of the opening in the bag through which the fecal material enters the bag, is connected with a solid annular coupling portion the cross section of which is approximately circular (in the specification called an O-ring) with a diameter as the axial width of the groove whereby it causes tightening when introduced into the groove; the wall of the groove farthest away from the abdominal wall of the patient and approximately parallel therewith effectively safeguards against unintentional release of the coupling at a uniform pull. The circular ring profile is connected with the bag, by means of a flat plate or disc extending radially outwardly relative to the O-ring. Accordingly, the engagement between the two annular coupling members is radial in contradistinction to the aforementioned axial engagements. The construction will not safeguard against local leakage a local pull on the bag at a limited part of the perimeter.
It is one object of the invention to avoid those drawbacks.
As mentioned, the ostomy equipment may optionally comprise an ostomy rod. In some cases of ostomy operations, e.g. when it is expected that the parts of the intestine downstream of the ostomy may later re-enter into its normal function, a loop of the intestine (bowel loop) is pulled outside the abdominal wall after the surgical opening thereof, a so-called transverse loop colostomy. Thereupon the loop is opened and sometimes its walls are sutured to the skin around the ostomy opening. Whether or not the bowel loop is sutured it is necessary during the initial period, normally 1-2 weeks, after the surgical operation, to support it mechanically to prevent, it from sliding back into the abdominal cavity or tearing the suture. An ostomy rod is used for this purpose. Originally there was used a glass rod which was placed under the bowel loop and with its ends abutting on the abdominal wall, outside the opening therein and under a bandage; often the rod was sutured to the skin. For many years ostomy rods have been made of plastics and moreover it has for many years been practice to place a bandage, frequently combined with a holding device for a bag for collecting fecal material, around the opening in the abdominal wall and under the ostomy rod, between the rod and the skin. It is normally necessary to replace the bandage once or a few times before the rod can be dispensed of, and it also has to be replaced if leakages occur so as to cause contact between intestinal waste and the skin.
Various forms of ostomy rods are known and commercially available. Claire Beresford describes in "Management of temporary colostomy", Nurse Times, 1981, 2:77, pp. 108-112, a rather rigid rod of circular cross section and provided with a short, stationary crossbar in one end and a corresponding, yet revolving crossbar in the other. When inserting and removing the rod into and from the position under the bowel loop the revolving crossbar is parallel with the rod but in the holding position perpendicular thereto; the crossbars serve for distributing the pressure on the abdominal wall and preventing the rod from sliding away from the holding position.
From DK patent specification No. 123689, which is equivalent to U.S. Pat. No. 2,483,868 to Marsan et al., there is known a colostomy equipment comprising a holding means for an ostomy bag. The holding means has a flange adapted to be secured to the abdomen of the patient around the artificial opening through which a transverse colostomy is projecting, and a ring projecting from the flange. The ostomy rod is adapted to be maintained in position with its ends in an internal annular groove in the ring. In order to be maintained in position in the internal annular groove, the end parts of the rod may be thinner than the remainder of the rod (which according to the drawing of the patent is cylindrical). In order to introduce the ends of the rod into the groove in the ring the latter is provided with at least two axial grooves, diametrically opposite each other, directed towards the annular groove either from the end of the ring adjacent the flange or the opposite end.
To place the equipment in position on the patient, the rod is inserted into one end of a flexible tube. The ends of the latter are conveyed through the central opening of the annular holding means. This is of the type where the axial grooves extend to the end of the ring farthest away from the flange and is guided over the bowel loop to place its flange so as to bear against the skin. Thereafter the flexible tube is pulled through (under) the bowel loop until the rod is so situated that approximately equal lengths thereof are visible on each side of the intestine. The tube is removed and the ends of the rod placed in the axial grooves. Finally the ring is turned round (about its axis) to be held securely in the internal annular groove. The possibility of turning the rod relative to the ring is strongly limited by its position perpendicular to the bowel loop. If the holding ring with its flange is combined with a bandage, which has been the practice for many years, it is almost impossible to revolve it because the bandage must be firmly connected to the ring and must also be adhesively affixed to the skin, in order to avoid leakage in the equipment and to avoid that intestinal fluid comes into contact with the skin.
Thus, the relative rotation of rod and ring causes big problems, and moreover it is necessary to ensure a very precise position of the ring relative to the rod before introducing the ends of the rod into the axial grooves, both with respect to the angular orientation of the rod relative to the ring and with respect to the position of the rod in its own longitudinal direction.
It is a further object of the invention to avoid these drawbacks. The said objects and further objects of the invention will be clear from the following description of the preferred embodiments of the invention.